On Mar 21, 3:52 pm, Vinzent Steinberg <vinzent.steinb...@googlemail.com> wrote: > Assumptions are currently borked in sympy (thus Fabian's rewrite). But Indeed. The whole assumptions part looks very messy. I tried to each of sympy.core.facts sympy.core.assumptions and sympy.core.basic to use the module I've written, and failed miserably. So now I'm making sympy.core.facts backward compatible, using a bunch of compatibility functions. I understand, this isn't very desirable but this should be much more bug free.
> I think by default x is not assumed to be real, so this should fail, > unless you defined x to be real. I suppose so, the docstring for class Symbol still says that its assumed to be real. .... class Symbol(sympy.core.basic.Atom) | Assumptions:: | real = True | commutative = True .... > > Fabian is currently implementing a lot of logic for the new > assumptions system, maybe you can join forces? He needs help with > implementing backward chaining. That'll be great! Looking forward to working with Fabian. A rewrite of the whole assumptions system should take a fairly long time, from what I reckon. > > Thank you for your work! > > Vinzent > > On Mar 20, 3:59 am, Akshay Srinivasan <akshaysriniva...@gmail.com> > wrote: > > > Its probably because of my crude merging. I have to tweak both > > sympy.core.assumptions as well as sympy.core.facts to make use of my > > module instead of sympy.core.logic . Turned out, taking the power of > > (-x) put it into a infinite loop. I'm still working on it. This isn't > > an issue with the current version. > > > As a sidenote, should this fail ? > > ((-x)**2)**Rational(1,3) == ((-x)**Rational(1,3))**2 > > Documentation for x says its assumed to be real. But neither ,>>>x.is_real > > >>>x.is_Real > > > False > > returns True. > > > 2009/3/20 Ondrej Certik <ond...@certik.cz>: > > > > On Thu, Mar 19, 2009 at 10:41 AM, Akshay Srinivasan > > > <akshaysriniva...@gmail.com> wrote: > > > >> Yes it worked! Thanks for the patch Ondrej, that did it. > > > > Well, but still it's fishy. Could you please execute that test by > > > hand? E.g. undo the patch and do: > > > > bin/test sympy/core/tests/test_arit.py -k test_pow2 > > > > if it hangs, then try to execute that code of the test in ipython and > > > let me know which exact line hangs. This signals some bug somewhere, > > > so we should fix it. > > > >> I'm beginning to wonder if making sympy.core.facts to use the module I > > >> wrote , is a good idea. From some initial tests, this seems to make > > >> the import time noticeably more. Of course I can't be sure that this > > >> is the reason- mainly because I haven't got it fully working. > > > > Maybe it's not a good idea -- but generally I think we should avoid > > > duplicate codes as much as possible. > > > > Ondrej > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy-patches" group. To post to this group, send email to sympy-patches@googlegroups.com To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en -~----------~----~----~----~------~----~------~--~---
